Abrasive recovery system

ABSTRACT

An abrasive recovery system comprising a perforated floor above a solid floor having a channel therein. Scraper assemblies are mounted above the solid floor for reciprocating movement across the floor toward and away from the channel. The scraper assemblies may be provided with pivoting blades adapted to pivot away from the floor when the scraper assemblies move away from the channel. A power source is connected to the scraper assemblies for reciprocation thereof. A conveyor may be located in the channel to convey collected abrasives away from the floor.

United States Patent 1191 1111 3,790,007 Sprague A Feb. 5, 1974 ABRASIVE RECQVERY SYSTEM Primary Examiner-RobertG. Sheridan [76] Inventor. Brlnton S rague, R. 5, Box 5821,

Bainbridg: Island wash. 981 10 Attorney, Agent, or Firm-Ralph R. Browning N 9, 1971 [22] Filed ov ABSTRACT 7, [211 App] No 19 089 An abrasive recovery system comprising a perforated floor above a solid floor having a channel therein. Cl 17 198/224 Scraper assemblies are mounted above the solid floor [51] Int. Cl. 824C 7/00, B65g 25/08 for reciprocating movement across the floor toward [58] Field Of Searc -m 17 17 17 and away from the channel. The scraper assemblies 1 5 /9, 198/224 may be provided with pivoting blades adapted to pivot v away from the floor when the scraper assemblies move References Cited away from the channel. A power source is connected UNITED STATES PATENTS to the scraper assemblies for reciprocation thereof. A 3 077 996 2/1963 Hollmeyer 214 1 A Conveyor y be located in the channel to convey col- 3,530,832 9 1970 Satnick 198/224 x lected abrasives y from the floor 961,486 6/1910 Dewey 198/224 1,426,648 8/1922 Johns 198/224 x 8 Clam, 5 awmg F'gures PATENTED 5 74 sum 2 or 2 BRl/VTON SPRA GUE Wm 21" F? INVENTOR.

I ATTORNEY I floor when moving in the reverse direction.

ABRASIVE RECOVERY SYSTEM BACKGROUND OF THE INVENTION l. Field of the Invention The present invention pertains to abrasive blasting apparatus. In particular, it relates to the recovery of spent abrasives in an abrasive blasting system.

2. Description of the Prior Art Abrasive blasting systems are well known in the art and frequently used in industry. For example, abrasives such as sand or other natural or synthetic materials have been used many years for cleaning various objects or for treating the surface of various materials in some other manner. For example, abrasive blasting systems are sometimes used in etching glass. Usually, the sand or other abrasive, is carried in a stream of air or water, at high velocitiesfor impingement against the object to be treated. Depending on the particular system and the value of the abrasives, recovery systems are provided whereby the spent abrasives may be recovered and processed, if necessary, for reuse.

Sand, being the most economical and sometimes the most effective, is the most commonly used abrasive. However, other abrasives such as metal pellets or nietallic granules, are preferred for certain treatments. In addition, the use of-metallic granules reduces dust,'silicosis and other associated hazards. However, metallic to sand recovery and are not suitable for recovery of metallic abrasives. Furthermore, improvements can-be made even in the systems designed specifically for sand recovery. For a general review of various types of abrasive blasting system with recovery apparatus reference is made to the following U.S. Pat. Nos.:

2,224,647 Grocholl 2,935,820 Mead 2,304,071 Bollinger 3,026,789 Mead 2,628,455 Webster. 3,309,818 Brown SUMMARY OF THE INVENTION The abrasive recovery system of the present invention is preferably enclosed in a building and comprises a grating or perforated floor above which the blasting operation is performed. Below the grating is a solid floor onto which spent abrasives may fall, after passing through the grating. A set of collector flights or scrapers are mounted for movement across the floor to scrape abrasives deposited on the floor toward a central collection channel in the floor. Mounted for longitudinal movement in the collection channel is another set of scrapers, or other type conveyor, for transferring the abrasives collected in the collection channel to a conveyor adjacent to the floor, whereby the spent abrasive materials may be conveyed to a location or treatment area appropriate for reuse. The collector flights and collection channel blades may be connected by means of cables to a suitable power source adapted for moving the cables first in one direction then another. Both the collector flights and the central collection channel blades may be adapted to pivot away from the scrape in one direction only.

The recovery system of the present invention is very simple to operate, economical to manufacture, and is highly efficient. Other objects and advantages of the invention will become apparent from the following description and accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS In the description of a preferred embodiment which follows, reference will be made to the accompanying drawings in which FIG. 1 is a plan view of the recovery system of the invention, as viewed from above, with most of the grating broken away;

FIG. 2 is a partial view in elevation and in section of the recovery system shown in FIG. 1, taken along line 22 thereof; 7

FIG. 3 is an enlarged fragmentary sectional elevation view, similar to the. view in FIG. 2, but showing greater detail of the invention;

FIG. 4 is an elevation view in section, showing the pivotal mounting of collector scraper blades utilized in the invention; and

FIG. 5 is a fragmentary sectional view of the pivotal mounting of FIG. 4 taken along line 55 thereof.

DESCRIPTION OF A PREFERRED EMBODIMENT Referring first to FIGS. 1, 2 and 3, there is shown apparatus for recovery of spent abrasives in an abrasive blasting system. Although it is not necessary, this apparatus would normally be enclosed in a room or building. A grating or perforated floor is supported above a solid floor 12 by a support frame which may include longitudinal beams 21, cross beams 22, and angle member 23, or any other suitable framing construction. Blasting would take place above grating 10, on which would be supported the workers, the blasting equipment, and the work to be blasted. Longitudinal rails might be provided for transporting work or blasting equipment to and from the blasting area. As spent abrasives' fall from the blasting work, they' drop through the perforated floor or grating 10 onto the solid floor 12.

To recover or collect the spent abrasives or granules, a set of collector flights or scraper assemblies are provided for reciprocating movement across the floor 12. As best see in FIGS. 3, 4 and 5, these scraper assemblies 30 may comprise lateral blades 31 supported on a frame including lateral cross members 35 and longitudinal members 36 (also see FIG. 1). The ends of cross members 35 may be provided with slide pads 38 adapted for sliding engagement with longitudinal rails 39 supported by floor 12. Thus, the entire scraper assembly 30 may bemoved toward or away from a cen- Thus they tral collection channel 14 by sliding along the rails 39. The longitudinal member 36 of the scraper assembly prevents the blades 31 from being cocked out of alignment or becoming disengaged from the rail 39. A cable and pulley arrangement comprising cables 41-45 and pulleys 51-58 connected to a Wench 61 and power unit 60 provides a means for reciprocating the scraper units levered shaft members 73 attached to the blades 31 by bolts 74. The upper portion of each blade 31 is provided with a slot or aperture 33 through which one of the cables 43, 44, 45 passes. Attached to the cable 45 at axially spaced positions is a pair of collar members 77, 78. These collar members 77, 78 are of a diameter greater than the width of aperture 33. Thus, when the cable 45 is moved in the scraping direction, to the left in FIG. 4, one of the collars 78 engages the back of blade 31 and causesblade 31 and the entire scraper assembly 30 to be pulled across floor 12, scraping the spent abrasives 18 toward the central collection channel 14. Although the force from cable 45 tends to pivot the blade about the axis of shaft 73a, the cross frame member 35 stops the blade 31 in the solid line position of FIG. 4. When the forward or scraping stroke is completed, the cable 45 is pulled in the opposite direction, I

toward the right in FIG. 4. When pulled in this direction, the collar 77 engages the front side of blade 31 and since there is nothing to prevent it from doing so, the blade 31 is pivoted towards the dotted line position of FIG. 4. In this position, the lower edge of the blade is raised away from the floor 12, preventing the blade from scraping abrasives away from the channel 14 on the return stroke. When the return stroke is completed, the cable 45 and collar 78 will return the blade 31 to its scraping position.

When the spent abrasives reach the central collection channel 14 they are transported through the channel, by another set of scraper assemblies 90, to an elevator or conveyor 100 for further transportation and processing. The elevator 100 may comprise a bucket type conveyor 101. The collection channel scrapers 90 may be similar to the floor scraper assemblies 30, but employing pivoted blades 91 of a length substantially less than the floor scraper blades 31. The collection scraper assemblies 90 could be reciprocated by cable and pulley arrangements 95, 96, 97 connected to wench 61 in a manner similar to the floor scrapers 30. Other types of conveyor assemblies could be used in the central collector channel 14. For example, a continuous belt conveyor would be suitable.

In summary, as the spent abrasives drop through the grating 10 on the floor 12, the floor scraper assemblies 30 are reciprocating back and forth across the floor 12. In the forward or scraping stroke, the blades 31 scrape the abrasives toward the central collection channel 14. In the reverse stroke, the blades 31 are pivoted away from the floor and do not disturb the abrasives. When the abrasives reach the channel 14, they are transported laterally by the scraper assemblies 90 toward the side where they are picked up by the elevator assembly 100 for further transportation and processing if neccessary. I

As can be seen from the foregoing description, the recovery apparatus of the present invention is very efficient. Substantially, the entire floor area 12 is scraped by the scraper assemblies 30. No complicated air or water collection apparatus is required. Nor does the recovery system of the present invention rely on gravity collection. In short, it is a very efficient, simply operated and economically manufactured recovery system.

Although only one embodiment of the invention has been described herein, many variations thereof will be apparent to those skilled in the art. For example, the scraper assemblies 30 and/or 90 could be wired to electrical apparatus for electromagnetizing the blades so as to attract metallic granules, as the blades move across the floor. The magnetism couldbe removed at collec tion points to allow separation of the granules from the blades. Even though the exemplary embodiment of the invention has been described for use with metallic blasting systems it may be used with other types of blasting materials. It is therefore intended that the scope of the invention be limited only by the claims which follow.

I claim:

1. An abrasive recovery system comprising:

a. a floor above which blasting work is performed;

b. a collection channel in said floor;

c. rail means disposed above said floor;

d. a frame member comprising lateral members connected by at least one longitudinal member, said frame member adapted for longitudinal movement on said rail means;

3. at least one scraper means for moving spent abrasive away from said floor to said channel, said scraper means including mounting means for pivotally connecting said scraper means to one of said lateral members, said frame member further having stop means thereon for limiting the pivoting movement of said scraper means;

f. cable means attached to said scraper means for effecting said pivoting movement, said cable means having means thereon engageable with said scraper means for maintaining the scraping edge of said scraper means adjacent said floor when said scraper means is moving toward said channel and for maintaining the scraping edge of said scraper means away from said floor when said scraper means is moving away from said channel;

g. conveyor means in said channel for moving said spent abrasive collected in said channel away from said floor.

2. The system of clain 1 wherein said mounting means comprises a bearing member and a shaft member, said shaft member having its axis parallel to the surface of said floor.

3. The system of claim 1 wherein said frame member is adapted for sliding movement on said rail means.

4. The system of claim 1 wherein said channel lies substantially across the center of said floor and there are scraper means disposed on each side of said channel.

5. An abrasive recovery system comprising:

a. a perforated first floor above which blasting work is performed;

b. a second floor below said first floor for catching spent abrasives falling from said blasting work;

0. a collection channel in said second floor;

d. rail means disposed above said second floor;

e. a frame member comprising lateral members connected by at least one longitudinal member, said frame member adapted for longitudinal movement on said rail means;

f. at least one scraper means for moving spent abrasive away from said second floor to said channel, said scraper means including mounting means for pivotally connecting said scraper means to one of said lateral members, said frame member further having stop means thereon for limiting the pivoting movement of said scraper means;

g. cable means attached to said scraper means for effecting said pivoting movement, said cable means having means thereon engageable with said scraper means for maintaining the scraping edge of said scraper means adjacent said floor when said scraper means is moving towards said channel and for maintaining the scraping edge of said scraper means away from said floor when said scraper means is moving away from said channel;

h. power means connected to said cable means for effecting said pivoting movement and said longitudinal movement of said frame member.

6. The system of claim 5 wherein said cable means passes through an aperture in said scraper means and wherein said means on said cable means engageable surface of said floor. 

1. An abrasive recovery system comprising: a. a floor above which blasting work is performed; b. a collection channel in said floor; c. rail means disposed above said floor; d. a frame member comprising lateral members connected by at least one longitudinal member, said frame member adapted for longitudinal movement on said rail means;
 3. at least one scraper means for moving spent abrasive away from said floor to said channel, saId scraper means including mounting means for pivotally connecting said scraper means to one of said lateral members, said frame member further having stop means thereon for limiting the pivoting movement of said scraper means; f. cable means attached to said scraper means for effecting said pivoting movement, said cable means having means thereon engageable with said scraper means for maintaining the scraping edge of said scraper means adjacent said floor when said scraper means is moving toward said channel and for maintaining the scraping edge of said scraper means away from said floor when said scraper means is moving away from said channel; g. conveyor means in said channel for moving said spent abrasive collected in said channel away from said floor.
 2. The system of clain 1 wherein said mounting means comprises a bearing member and a shaft member, said shaft member having its axis parallel to the surface of said floor.
 3. at least one scraper means for moving spent abrasive away from said floor to said channel, saId scraper means including mounting means for pivotally connecting said scraper means to one of said lateral members, said frame member further having stop means thereon for limiting the pivoting movement of said scraper means; f. cable means attached to said scraper means for effecting said pivoting movement, said cable means having means thereon engageable with said scraper means for maintaining the scraping edge of said scraper means adjacent said floor when said scraper means is moving toward said channel and for maintaining the scraping edge of said scraper means away from said floor when said scraper means is moving away from said channel; g. conveyor means in said channel for moving said spent abrasive collected in said channel away from said floor.
 3. The system of claim 1 wherein said frame member is adapted for sliding movement on said rail means.
 4. The system of claim 1 wherein said channel lies substantially across the center of said floor and there are scraper means disposed on each side of said channel.
 5. An abrasive recovery system comprising: a. a perforated first floor above which blasting work is performed; b. a second floor below said first floor for catching spent abrasives falling from said blasting work; c. a collection channel in said second floor; d. rail means disposed above said second floor; e. a frame member comprising lateral members connected by at least one longitudinal member, said frame member adapted for longitudinal movement on said rail means; f. at least one scraper means for moving spent abrasive away from said second floor to said channel, said scraper means including mounting means for pivotally connecting said scraper means to one of said lateral members, said frame member further having stop means thereon for limiting the pivoting movement of said scraper means; g. cable means attached to said scraper means for effecting said pivoting movement, said cable means having means thereon engageable with said scraper means for maintaining the scraping edge of said scraper means adjacent said floor when said scraper means is moving towards said channel and for maintaining the scraping edge of said scraper means away from said floor when said scraper means is moving away from said channel; h. power means connected to said cable means for effecting said pivoting movement and said longitudinal movement of said frame member.
 6. The system of claim 5 wherein said cable means passes through an aperture in said scraper means and wherein said means on said cable means engageable with said scraper means comprises a pair of axially spaced collar members attached to said cable on opposite sides of said scraper means.
 7. The system of claim 5 wherein said lateral members are adapted for engagement with said rail means to maintain substantially parallel alignment of said scraper means with said channel.
 8. The system of claim 5 wherein said mounting means comprises a bearing member and a shaft member, said shaft member having its axis parallel to the surface of said floor. 